Track unit for moving a ground work vehicle

ABSTRACT

A track unit for moving a ground work vehicle, comprising two elastic elements proximate to the front and rear ends, interposed between a monolithic upper portion of the structure that supports the driving wheel and a monolithic lower portion that supports two pairs of coaxial guiding wheels with parallel axles and resting rollers, means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure being also provided.

BACKGROUND OF THE INVENTION

It is known that several types of ground work vehicle, and we are referring for example to machines that work in the field of agriculture or of earth-moving machines or machines for geophysical research, are provided, instead of the wheels of at least one axle, with track units that comprise a structure for supporting a driving wheel that moves a track in contact with guiding wheels and resting rollers associated with said structure.

In certain types of track units, such supporting structure is monolithic, but there are also track systems in which the structure proper is divided into two portions connected by means of elastic coupling means in order to provide users with a certain comfort.

However, the background art provides embodiments of such track units that are not entirely satisfactory, and therefore the aim of the present invention is to provide a track unit that has great simplicity and maximum functional efficiency.

SUMMARY OF THE INVENTION

This aim is achieved by a track unit for moving a ground work vehicle, according to the invention, characterized in that it comprises the features given in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the track unit according to the invention will become better apparent from the description of two preferred but not exclusive embodiments thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:

FIG. 1 is a perspective view of the track unit according to the invention, with the track shown in dot-and-dash lines;

FIG. 2 is a side view of the track unit according to the invention, with a fairing and the track removed for reasons of illustration;

FIG. 3 is a view of a detail of FIG. 1, with a pair of rollers shown in dot-and-dash lines;

FIG. 4 is a side view similar to FIG. 2, according to another embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the FIGS. 1, 2, 3, the reference numeral 1 generally designates the track unit according to the invention, which comprises a supporting structure divided into two portions.

The first upper portion of the structure comprises two strong profiles 2 and 3, which are monolithically connected, with the corresponding plates 2 a, 3 a, such upper portion supporting the driving wheel 4 that moves the track 5.

The second lower portion of the structure comprises the longitudinal member 6 with the monolithically connected plates 6 a, 6 b, and such monolithic portion supports with parallel axles the front and rear guiding wheels of the track 5, and more precisely the front pair of coaxial wheels 7 a, 7 b and the rear pair of coaxial wheels 8 a, 8 b.

Such second portion 6 further supports the resting rollers that are mounted in pairs on four axles: the reference numerals 9 a, 9 b designate the rollers mounted on the first axle, the numerals 10 a, 10 b designate the rollers mounted on the second axle, and the numerals 11 and 12 designate two rollers mounted respectively on the third axle and on the fourth axle.

The portion of the track 5 that runs between the guiding wheels 7 a, 7 b and 8 a, 8 b, and at the resting rollers mounted on the four intermediate axles, is the one that makes contact with the ground.

Two elastic elements are interposed between the two monolithic structure portions described, are arranged respectively proximate to the front and rear ends and are formed by the monolithic blocks 13 and 14, which are made of elastic material and are coupled to the longitudinal member 6 and to the plates 2 a, 3 a, which are shown in FIG. 2, whereas in FIG. 1 they are hidden behind the fairing 15.

Moreover, there are means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure, such means comprising two linkages arranged respectively proximate to the front and rear ends and pivoted on said portions.

The front linkage, generally designated by the reference numeral 16, is articulated in an intermediate position by means of the pivot 16 a, and is pivoted to the upper and lower portions of the structure respectively by means of the pivots 16 b, 16 c; the rear linkage 17 is hinged to the upper and lower portions of the structure respectively by means of the pivots 17 a, 17 b, and also has the function of contrasting any longitudinal thrusts that are parallel to the ground and are generated on the lower portion and to which the elastic elements 13 and 14 are unable to provide any contrast.

The two front axles, i.e., those that support the resting rollers 9 a, 9 b and 10 a, 10 b, respectively, are connected by the spherical joint provided with a rocker, generally designated by the reference numeral 18 and shown in particular in FIG. 3, which is fixed to the lower portion of the structure by means of the threaded stems 18 a, 18 b, and a similar spherical joint, designated by the reference numeral 19, is interposed between the third axle and the fourth axle.

Advantageously, such spherical joints are of the elastic type.

FIG. 4 illustrates a further embodiment of the track unit according to the invention, in which between the upper portion of the structure that comprises the profiles 2 and 3 with the corresponding plates 2 a, 3 a and the lower portion that comprises the longitudinal member 6 with the corresponding plates 6 a, 6 b elastic elements are interposed, generally designated by the reference numerals 20 and 21, which are shaped so as to provide contrast to longitudinal thrusts that are parallel to the ground and might be applied to the lower portion of the structure.

The elastic element 20 comprises two components 20 a, 20 b, which are coupled respectively to the plate 2 a of the upper portion of the structure and to the longitudinal member 6 of the lower portion, and likewise the elastic element 21 comprises two components 21 a, 21 b, which are coupled respectively to the plate 3 a and to the longitudinal member 6, and the surface in mutual contact of said components, designated respectively by the reference numerals 20 c, 21 c, is V-shaped; in this manner, it is possible to generate a reaction for contrasting the longitudinal thrusts that are parallel to the ground as mentioned above, and it is barely worth noting that the surface in mutual contact of the two components can be contoured according to several shapes that are different from the one shown.

Of course, the means adapted to ensure the coplanar arrangement of the two portions of the structure are no longer involved in contrasting said thrusts, and therefore are shaped according to the two linkages 22, 23, which are articulated in an intermediate position by means of the pivots 22 a, 23 a and are hinged on the upper portion of the structure by means of the pivots 22 b, 23 b, respectively, and on the lower portion by means of the pivots 22 c, 23 c, respectively.

The described invention is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent elements.

The disclosures in Italian Patent Application No. MN2008A000012 from which this application claims priority are incorporated herein by reference. 

1. A track unit for moving a ground work vehicle, comprising a structure for supporting a driving wheel which is adapted to transmit motion to a track that has a portion, at two pairs of coaxial guiding wheels at the end and at intermediate resting rollers, which is in contact with the ground, wherein two elastic elements are provided located respectively proximate to the front and rear ends, interposed between a monolithic upper portion of said structure that supports the driving wheel and a monolithic lower portion that supports the two pairs of coaxial guiding wheels with parallel axles and the resting rollers, means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure being also provided.
 2. The track unit according to claim 1, wherein the means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure have such a shape as to contrast longitudinal thrusts that are parallel to the ground and are applied to said lower portion, the two elastic elements being provided so as to be irrelevant in this respect.
 3. The track unit according to claim 1, wherein the means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure have, proximate to the front and rear ends, respective linkages hinged on said portions, one of said linkages being articulated in an intermediate position, the two elastic elements being provided by means of monolithic blocks made of elastic material.
 4. The track unit according to claim 1, wherein the two elastic elements have such a shape as to provide the retention of longitudinal thrusts that are parallel to the ground and are applied to the lower portion of the structure.
 5. The track unit according to claim 1, wherein at least one of the elastic elements is shaped according to two components which are coupled respectively to the upper and lower portions of the structure, and are contoured at the surface in mutual contact so as to create a reaction contrasting longitudinal thrusts that are parallel to the ground on said lower portion, the means adapted to ensure a coplanar situation of said upper and lower portions of the structure being shaped according to two linkages articulated in an intermediate position being hinged at the front and rear ends of said portions.
 6. The track unit according to claim 5, wherein the two elastic elements are each shaped according to two components that are coupled respectively to the upper and lower portions of the structure and are V-shaped at the surface in mutual contact.
 7. The track unit according to claim 1, wherein at least one pair of axles is provided for supporting the resting rollers, a spherical joint being provided which is interposed between the axles of the pair and the lower portion of the structure.
 8. The track unit according to claim 1, wherein at least one pair of axles is provided for supporting the resting rollers, an elastic spherical joint being provided which is interposed between the axles of the pair and the lower portion of the structure. 